    Patent Literature 1: JP 3927168 B2
Patent Literature 1 discloses an entity recognition system including a camera that images a predetermined range, an accessory element that accompanies an entity in the real world, and a computer that wirelessly communicates with the accessory element and acquires a photographic image of the camera.
The accessory element in Patent Literature 1 emits light in responding to a light emission instruction command issued from the computer. The computer sequentially analyzes the photographic image of the camera, so as to detect the light emitted from the accessory element. The computer identifies the position of the entity accompanied by the accessory element, based on the position of emitted light in the photographic image. Accordingly, the computer identifies the association of the entity imaged using the camera, with the entity, which exists in the real world and is accompanied by the accessory element that wirelessly communicates with the computer.